Axially arranged rotary threshing or separating systems have long been in use in agricultural combines for threshing crops to separate grain from crop residue, also referred to as material other than grain (MOG). Such axially arranged systems typically include at least one cylindrical rotor rotated within a concave or cage, the rotor and surrounding concave being oriented so as to extend forwardly to rearwardly within the combine.
In operation, crop material is fed or directed into a circumferential passage between the rotor and the concave, hereinafter referred to as a rotor residue passage, and is carried rearwardly along a generally helical path in such passage by the rotation of the rotor as grain is threshed from the crop material. The flow of crop residue or MOG remaining between the rotor and concave after threshing is typically discharged or expelled by the rotating rotor at a rear or downstream end of the rotor and the rotor residue passage in a generally downward, or a downward and sidewardly, direction in what is a continuation of the helical path of movement of the crop residue within the rotor residue passage between the rotor and concave.
The flow is typically discharged into a discharge opening at the downstream end of the rotor and into a further passage, hereinafter referred to as a discharge passage, that extends downwardly and somewhat rearwardly into a crop residue distribution system located below and rearwardly of the rear end of the threshing system, and which typically includes a rotary beater or other apparatus which propels the crop residue rearwardly within a rear end of the combine for either discharge from the combine through a rear opening onto a field, or into a chopper and/or spreader mounted on the rear end operable for spreading the residue over a swath of a field.
Due to the nature of operation of the rotor, the design of the rotor and concave, and the helical movement of the crop residue within the rotor residue passage, the flow of crop residue from the rotor residue passage into the discharge opening is often greater on the downward sweep side of the rotor than on the upward sweep side, as a consequence of which an uneven flow of crop residue occurs across the width of the discharge opening, which uneven flow has typically, in the past, proceeded through the discharge passage to the crop residue distribution system.
When the crop residue is to be spread in a swath over a field, it is desirable in many instances for the crop residue to be distributed evenly or uniformly over the swath. This is desirable for reasons including that uneven crop residue distribution on a field can lead to temperature and moisture gradients detrimental to even growth of future crops on the field. It can also make it difficult for crops to utilize nutrients, and can impact the effectiveness of agricultural chemicals. Large discontinuities of crop residue can lead to plugging and other functional problems with tillage and/or planting equipment.
One factor which has been found to influence the ability of a chopper and/or spreader to distribute crop residue evenly or uniformly over a field is the transverse or side to side evenness of crop residue inflow into the chopper and/or spreader. That is, it has been found that the amount of crop residue infeed to one side of the chopper should be about equal to the amount of crop residue infeed to the other side in order to achieve even distribution over a field. In turn, the side to side infeed to the chopper/spreader has been found to be a function of the side to side distribution of crop residue infeed into the beater or other impeller of the crop residue distribution system from the threshing system.
Numerous devices and structures have been developed to improve flow of crop residue from axially arranged threshing systems into crop residue distribution systems, including constructions such as are disclosed in Payne et al. U.S. Pat. No. 6,352,474 entitled Metering Edge for Axially Arranged Rotary Separator and Pfeiffer et al. U.S. Pat. No. 6,241,605 entitled Discharge Geometry for Axially Arranged Rotary Separator.
Although the above referenced constructions may perform well, it has been found that a variety of variables and conditions can influence the ability to redirect and transversely distribute crop residue flow in the discharge passage between a threshing system and a crop residue distribution system. For example, residue from different crops, such as wheat and corn, will typically flow differently, and different rotor rotation speeds will typically be used for different crops. For instance, small grains such as wheat and other grasses will typically be threshed at a relatively high rotor speed, for instance, 600 to 1000 revolutions per minute (rpm), and produce residue containing a large volume of small stalks of straw, whereas corn will typically be threshed at a relatively slow rotor speed, for instance, less than 400 rpm, and produce crop residue containing a mixture of bulky stalk segments, cob fragments and large leaves. For a given crop, differences in plant maturity and weather conditions can affect size, moisture content, and other characteristics of crop residue so as to have varying flow and distribution characteristics.
Due at least in part to the above described variables and conditions, it has been observed that the transition of crop residue flow from the threshing system to the residue distribution system can vary. In particular, the side to side distribution of the flow into the rotating beater can vary, that is, flow to one side of the beater can be heavier than to the other side, such that the beater will propel more crop residue into one side of a chopper and/or spreader, resulting, in turn, in uneven crop residue distribution over a swath of a field.
In an attempt to address the foregoing problems, an apparatus was thus developed for transitioning crop residue from an axially arranged threshing system of a combine to a distribution system that overcomes one or more of the problems and disadvantages set forth above. Such apparatus, as described in co-pending U.S. patent application Ser. No. 11/204,230, includes an adjustable deflector construction that includes a movable portion, hereinafter referred to as a deflector plate, that can be adjustably positioned to be in the path of the flow of the crop residue when that residue is expelled from the threshing system and an adjusting mechanism operable for moving the deflector plate within the path of the flow of the crop residue for changing a transverse location at which the flow deflected by the deflector plate will flow into the crop residue distribution system. For the most part, prior to the present invention, deflector constructions have been positioned with the deflector plate hingedly or pivotally mounted at the downstream end of the rotor adjacent a lower quadrant of the rotor residue passage, and adjustment thereof has been performed either manually or under control of a control system.
It has now been discovered and recognized that improved performance and reliability can be achieved through the employment of additional features and methods, including by locating the deflector at a higher position at the downstream end of the rotor, with the hinge or pivoting axis for the deflector plate being at approximately the height of the axis of the rotor at its downstream end, and by also providing a control that will effect automatic retraction of the deflector to a nominal, safe, typically approximately vertical position, when a rotor reversing function is engaged, such as when the rotor has become plugged and actuation of a rotor reversing function or deplugging function is effected to clear the plug. By positioning the deflector plate in the discharge passage at the downstream end of the threshing rotor at such higher position at approximately the height of the axis of the threshing rotor at that downstream end, crop residue can be intercepted at an earlier and generally higher point of discharge and redirected as determined to be desirable to better distribute the crop residue, and especially to better direct a portion of the residue stream from the heavier flow side towards the lighter flow side of the spreader.
The noted, controlled retraction of the deflector plate prevents damage to the deflector apparatus by the crop residue and the rotor that might otherwise be occasioned by the change in the rotor's direction of rotation. In the absence of such controlled retraction, a rotor reversal can result in the forced deposit of crop residue between the backside of the extended deflector plate and the bulkhead to which it is mounted and the attendant risks of damage to both the deflector plate itself and to the adjustment means therefor as additional crop residue continues to be directed to such location. Even if the rotor reversal is only for a short duration, when the rotor operation is returned to its original condition, the buildup of crop residue between the backside of the deflector plate and the bulkhead to which it is mounted may be such that it does not properly clear, which can result in the deflector plate remaining in a jammed condition or in subsequent less effective operation and positioning of the deflector plate.
Additionally, it has been found that the inclusion of a projecting directional vane on the surface of the deflector plate and a tapered leading edge can both individually further assist in distributing the crop residue more evenly, and that it is also advantageous to be able to return the deflector plate to a desired, operating condition after the rotor reversing function has been completed or disengaged, such as the operating position prior to rotor reversal.
Consequently, there has now been developed an improved apparatus, and method of use thereof, for transitioning crop residue from an axially arranged threshing system of a combine to a distribution system that includes one or more of the features discussed hereinabove and which overcomes one or more of the problems and disadvantages set forth hereinabove.